Travel from Florence to Switzerland

How about Stresa
A town on Lake Maggiore, views, islands to visit (Borromean Islands) and lake ferries. It is in Italy (so technically not a Swiss-Mountain feel). It is actually on the rail line from Milan to Spiez, the trains go through Stresa, so not time-wasting detour.

Stresa website: https://www.stresa.com/
Page on Borromean Islands: https://www.stresa.com/borromeanislands

This one is a bit out of your way, but hear me out.

Check out the Bernina Express. Its the most scenic train ride I've been on in Europe, and the train takes full advantage with panoramic windows, and a stop at one of the highest stations in Europe. Google it and you'll see the pictures.

Downside is to get to the Berner Oberland, your connections would be: Florence > Milan > Tirano > Bernina Express to Chur > Luzern > Interlaken > Lauterbrunnen.

If you’re going to Lauterbrunnen you may as well keep going up up up to the car-free alpine villages of either Murren or Wengen. They’re spectacular.

We’ve done the trek from Florence to Murren and from Venice to Murren and even though it’s a few hours spent traveling it’s not difficult.

I really second the recommendation for Stresa; the Borromean Islands on Lake Maggiore are truly a sight to see and enjoy!

Chris's suggestion of Stresa is a great one if you are looking to split up the trip.

Its pedantic but the 3 connections for the fastest way are connections at Milan, Spiez, and Interlaken Ost. The 8:55 am departure from Florence S.M.N station gets you to Lauterbrunnen at 2:55 pm, exactly 6 hours. The train from Milano Centrale station stops at Stresa at 12:20 pm, making it 3 1/2 hours after departing Florence, so it is a bit over half way.

I agree with the two earlier posters about Stresa. It's worth a stopover to see the Borromean Islands. Villa Pallavicino, with lawns, greenhouses and gardens, in addition to deer and lamas roaming freely is another destination to visit in Stresa.

http://en.lagomaggiore.net/38/villa-pallavicino.htm

Another option is to stay in Lugano. That lake is also beautiful and visit the neaby town of Bellinzona Switzerland.

https://www.myswitzerland.com/en-us/destinations/bellinzona/

You can train from Lugano to Lauterbrunnen Valley.

It is 4 hours 51 minutes from Lugano to Lauterbrunnen, so that is just an hour and 10 minutes shorter than doing it as one shot from Florence to Lauterbrunnen. Lugano is a city in Switzerland, so it will be quite a bit more expensive as a stopover vis-a-vis Stresa in Italy.

kaime,

The trip from Florence to Lauterbrunnen is relatively easy, and I wouldn't hesitate in doing that trip in one day. Although an intermediate stop will break the trip up and allow you to see another place, you'll probably enjoy your time in the Berner Oberland more. If I were making that trip, I'd use a departure from Firenze SMN at 09:00, arriving Lauterbrunnen at 14:55 (time 5H:55M, 3 changes, last segment from Interlaken Ost to Lauterbrunnen via Post Bus). I've been staying in Lauterbrunnen on the last few trips, as it's the transportation hub in that area so makes a great "home base" for touring both sides of the valley.

Thank you all so much! The places mentioned look beautiful and I'm glad to hear it is not a bad trip if we decide to go straight there.

I forgot to mention in my original post, we are planning this trip in the last two weeks of May (Switzerland in the second half). I saw in a TripAdvisor forum someone said that May is not a good time to visit the Lauterbrunnen area as most things are closed and it is muddy and icy. Has anyone visited this area in May before? If it is not a good idea, are there any other areas in Switzerland you'd recommend over Lauterbrunnen to see the Alps?

May is fine, don't worry. Especially later in May. Sure, you can have some mud and patches of snow at higher elevations, some hotels and restaurants will be closed (but not all!), but the mountains will still be there in all their glory and a fair chance of good weather.
Lauterbrunnen is a good place to stay but I would also consider higher-elevation villages like Mürren.